Filament not extruding
Hello forum,
I have a newly assembled Prusa i3 mk3 printer that I purchased in kit form. The self test, xyz calibration and z calibration have run fine.
When I insert the filament it goes 4cm into the extruder, then when I select "Preheat" and "Load filament" the filament goes 1-2 cm more inside the extruder. Then when I run the first layer calibration nothing is printed, no filament is extruded.
I repeated the process of inserting the filament this time helping the stepper motor pushing the filament with my fingers. This time I can make the filament go aprox 11-12 cm inside the extruder. When running the selftest just a small thin filament like a hair came out of the nozzle like you see in the attached image.
How can this be solved?
Thanks.
Re: Filament not extruding
Clog in hot end. Here we go again.
First try a "cold pull"
Preheat hot end to 245C (because it is probably PETG debris)
Insert your filament manually with and advance it to where you get that little bit coming out again.
Let hot end cool to below 120C
Open extruder idler door.
While applying about 1 kg or 2 lb upward tension on filament, start heating hot end to 220C.
Keep upward tension on filament. At some point during heating, you will be able to pull up the filament and hopefully the stuck debris.
If two or three cold pulls don't clear the hot end, you get to take the extruder apart (post a cold pull) and manually clear the obstruction.
Be careful not to break the heater and thermistor wires. Probably best to release the zip ties to reduce breakage risk.
Re: Filament not extruding
Check that the extruder is correctly mounted. If it is not able to feed down the filament then it is something that needs to be corrected.
Are the two Bondteck pulley mounted correctly.
Because you can manually feed the filament, I don't think you have a glogg. Some pictures of Bondtech and Extruder idler say more than a thousand words.
Bear MK3 with Bondtech extruder
Re: Filament not extruding
I could only get time to post some photos of the pulleys in the extruder today. Is there anything wrong there?
Re: Filament not extruding
Maybe it's just an angle. Are the gears and PTFE tube perfectly aligned? Looks a little bit off
Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram
Re: Filament not extruding
Third image appears to show the Bondtech gear is completely out of line with the centre of the ptfe tube. No way that will feed filament correctly. Your Bondtech gears need to be moved so that the filament path is all directly in line vertically. Have a look at that section in the build instructions.
Re: Filament not extruding
Agree. The Bondtech pulley is well out of alignment. Do as Olef says, get that pulley properly positioned on the motor shaft.
Filaments should pass straight down from top of extruder into PTFE tubing. The gear's hobbed section should be positioned to align with the filament path.
Re: Filament not extruding
I would also recommend that you remove the extruder and install the Teflon tube correctly. It should not sit so high up against the Bondtech wheels.
If you do not fix it, you will have problems with glogs and filament replacement.
The Teflon tube should be pressed down in hot end while lifting the black ring at the top of the hot end. Then the teflon tube is locked in the correct position.
Bear MK3 with Bondtech extruder
Re: Filament not extruding
Personally I pre-heat for 10 minutes or so, well before I even load the filament. Then I help with a little push of the filament after it goes meets the PTFE tubing - you can feel it slightly hit the countersinking , or at least I can.
Texy
Re: Filament not extruding
thank you all guys for your replies that helped me so much.
I could move the pulley along the motor axis a bit to the right using the pliers until it got aligned with the tube and after that the motor is able to pull the filament well.
Now I've been able to finish the first layer calibration successfully. Then I've tried the Prusa logo print and it was working well until after it printed the first 3 layers the print unsticked and got off the steel sheet.
I've posted a photo, but anyway I think it is better that I make another post to continue with this new problem I'm facing. I'll do a bit more investigation and if I don't come with a solution I'll start a new post.
RE: Filament not extruding
I think I have a similar problem but I'm going to have to take apart the extruder because it looks like pla pouring out of the top of the hot end and also my cables seem to be hanging low for some reason.
I saw an extruder disassemble link for an upgrade. Anyone no a good link when its to fix this issue. I don't want to make the situation worse
RE: Filament not extruding
@elliotschroeder
Please check out this guide if you have the MK3S: https://help.prusa3d.com/en/guide/how-to-replace-a-ptfe-tube-mk3s-mk2-5s-mmu2s_21664
or this guide if you have the MK3: https://help.prusa3d.com/en/guide/how-to-replace-a-ptfe-tube-mk3-mk2-5_17360
For either case, please follow the steps up to and including step 5 in order to free up the hotend and post a picture of the situation. Be careful when moving the hotend out of the extruder body since the wires attached to the thermistor and heater cartridge are fragile.
RE: Filament not extruding
Be careful when moving the hotend out of the extruder body since the wires attached to the thermistor and heater cartridge are fragile.
Isn't that the truth!
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Chuck H
3D Printer Review Blog
RE: Filament not extruding
@daniel-s89
Thanks, let me block off some time and have a go at it
RE: Filament not extruding
Thanks guys this helped a lot. When I disassembled it I didn't see any issues but then saw some filament in the tube that I pushed out, maybe some melted stuff got pulled up and it dried because it required pushing it out with the hex wrench. Ended up just replacing the tube. Started it up and got it extruding. Thanks!
RE: Filament not extruding
Well it worked for a bit. Then I ran into the issue again.
One thing I noticed is that for some reason near the top of the new tube there is some resistance with PLA so it doesn't slide easily. Should the tube be lubricated?